US will be performed for 20 healthy controls and 20 patients with RA. US scan will be fulfilled symmetric both sides. Diagnosis RA is relied on anamnesis data, physical examination, and laboratory findings. Synovial swelling, synovial tenderness, local fever of joint region, active and passive limitation, accelerated erythrocyte sedimentation rate(ESR) upper 40mm/hr (N<12), C reactive protein (CRP) upper 1.5mg/dl (N<0.5) were clinical signs of active inflammation. Twenty healthy controls did not complain of shoulder pain and limitation and their physical examination was unremarkable.